package org.apache.solr.schema;

/**
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import org.apache.solr.common.SolrException;
import org.apache.solr.common.params.MapSolrParams;
import org.apache.solr.common.params.SolrParams;
import org.apache.solr.search.QParser;
import org.apache.lucene.search.Query;

import java.util.HashMap;
import java.util.Map;

/**
 * An abstract base class for FieldTypes that delegate work to another
 * {@link org.apache.solr.schema.FieldType}. The sub type can be obtained by
 * either specifying the subFieldType attribute or the subFieldSuffix. In the
 * former case, a new dynamic field will be injected into the schema
 * automatically with the name of {@link #POLY_FIELD_SEPARATOR}. In the latter
 * case, it will use an existing dynamic field definition to get the type. See
 * the example schema and the use of the
 * {@link org.apache.solr.schema.PointType} for more details.
 * 
 **/
public abstract class AbstractSubTypeFieldType extends FieldType implements
		SchemaAware {
	protected FieldType subType;
	public static final String SUB_FIELD_SUFFIX = "subFieldSuffix";
	public static final String SUB_FIELD_TYPE = "subFieldType";
	protected String suffix;
	protected int dynFieldProps;
	protected String[] suffixes;
	protected IndexSchema schema; // needed for retrieving SchemaFields

	public FieldType getSubType() {
		return subType;
	}

	@Override
	protected void init(IndexSchema schema, Map<String, String> args) {
		this.schema = schema;
		// it's not a first class citizen for the IndexSchema
		SolrParams p = new MapSolrParams(args);
		String subFT = p.get(SUB_FIELD_TYPE);
		String subSuffix = p.get(SUB_FIELD_SUFFIX);
		if (subFT != null) {
			args.remove(SUB_FIELD_TYPE);
			subType = schema.getFieldTypeByName(subFT.trim());
			suffix = POLY_FIELD_SEPARATOR + subType.typeName;
		} else if (subSuffix != null) {
			args.remove(SUB_FIELD_SUFFIX);
			suffix = subSuffix;
		} else {
			throw new SolrException(SolrException.ErrorCode.SERVER_ERROR,
					"The field type: " + typeName + " must specify the "
							+ SUB_FIELD_TYPE + " attribute or the "
							+ SUB_FIELD_SUFFIX + " attribute.");
		}

	}

	/**
	 * Helper method for creating a dynamic field SchemaField prototype. Returns
	 * a {@link SchemaField} with the {@link FieldType} given and a name of "*"
	 * + {@link FieldType#POLY_FIELD_SEPARATOR} + {@link FieldType#typeName} and
	 * props of indexed=true, stored=false.
	 * 
	 * @param schema
	 *            the IndexSchema
	 * @param type
	 *            The {@link FieldType} of the prototype.
	 * @return The {@link SchemaField}
	 */

	static SchemaField registerPolyFieldDynamicPrototype(IndexSchema schema,
			FieldType type) {
		String name = "*" + FieldType.POLY_FIELD_SEPARATOR + type.typeName;
		Map<String, String> props = new HashMap<String, String>();
		// Just set these, delegate everything else to the field type
		props.put("indexed", "true");
		props.put("stored", "false");
		props.put("multiValued", "false");
		int p = SchemaField.calcProps(name, type, props);
		SchemaField proto = SchemaField.create(name, type, p, null);
		schema.registerDynamicField(proto);
		return proto;
	}

	public void inform(IndexSchema schema) {
		// Can't do this until here b/c the Dynamic Fields are not initialized
		// until here.
		if (subType != null) {
			SchemaField proto = registerPolyFieldDynamicPrototype(schema,
					subType);
			dynFieldProps = proto.getProperties();
		}
	}

	/**
	 * Throws UnsupportedOperationException()
	 */
	@Override
	public Query getFieldQuery(QParser parser, SchemaField field,
			String externalVal) {
		throw new UnsupportedOperationException();
	}

	protected void createSuffixCache(int size) {
		suffixes = new String[size];
		for (int i = 0; i < size; i++) {
			suffixes[i] = "_" + i + suffix;
		}
	}

	protected SchemaField subField(SchemaField base, int i) {
		return schema.getField(base.getName() + suffixes[i]);
	}
}
